Load control systems may include one or more sensors configured to communicate with a load control device to effect an operation of the load control device. A sensor may cause the load control device to switch or dim an associated electrical load (e.g., a lighting load). In this regard, the sensor may operate as a control device with respect to a load control device. Examples of such sensors include light sensors, shadow sensors, occupancy/vacancy sensors, temperature sensors, and the like. Such sensors may be configured to be attached to one or more surfaces, such as a wall or ceiling, for example.
FIG. 1 depicts an example load control system 10. As shown, the load control system 10 includes a load control device 20 (e.g., a dimmer switch) and a battery-powered sensor 50 (e.g., a daylight sensor). The sensor 50 includes a housing 52 having a base portion 54 and a cover portion 56 that is releasably attached to the base portion 54. The load control device 20 is configured to be coupled in series electrical connection between an alternating current (AC) power source 30 and an electrical load 40 (e.g., a lighting load) for controlling the amount of power delivered to the electrical load 40. The load control device 20 may be mounted, for example wall-mounted in a standard electrical wall box.
The sensor 50 may be associated with (e.g., assigned to) the load control device 20, for example during a setup procedure of the RF load control system 10. The sensor 50 may be configured to wirelessly communicate digital messages to the load control device 20, for example via radio-frequency (RF) signals 60.
A sensor may be battery powered, and may include a battery holder configured to retain the battery in the sensor. Battery holders of known sensors may be configured such that the battery may be removed from the battery holder via a single motion. FIG. 2 depicts an example prior art battery holder 70 that may be used with a battery-powered sensor (e.g., the sensor 50 depicted in FIG. 1). As shown, the battery holder 70 may include a cradle 72 configured to at least partially retain a battery 120 within the battery holder 70. The cradle 72 may include a wall 74 that extends around a portion of a perimeter of the cradle 70. The wall 74 may define an opening 76 through which the battery 120 can be inserted into, or removed from, the cradle 70.
The battery 120 may be removed from the battery holder 70 using a single motion. For example, the battery 120 may be slid out of the cradle 70 by applying a force F to the battery 120 along a direction radially outward from the center of the cradle 70, toward the opening 76. The force F may be applied to the battery 120 using a finger, for example, which may cause the battery 120 to slide out of the battery holder 70 through the opening 76. An example of a sensor having a battery holder similar to the battery holder 70 depicted in FIG. 2 is described in greater detail in U.S. Patent Application Publication No. 2011/0139965, published Jun. 16, 2011, entitled DAYLIGHT SENSOR HAVING A ROTATABLE ENCLOSURE, the entire disclosure of which is incorporated herein by reference.
Ease of battery removal from the battery holder of a sensor may be desirable, for example from an end user perspective, but makes the sensor vulnerable to having the battery become separated from the battery holder undesirably. For example, if the battery holder is dropped, an impact force imparted to the battery holder may cause the battery to be ejected from the battery holder.